Dave,

Your solution is probably adequate, but here are a few ideas:

1. if you're running line level audio you may want to run shielded 2-conductor instead of RG-59. The problem with 59 is that you have signal current running through the shield so any stray EMI that's out there will be directly coupled to your audio.

2. I would also suggest spending a little money and ordering cable that is already terminated. Crimpless connectors sound like a good idea, but in practice they can be hard to attach and be the source of all kinds of mysterious problems. Just order cables that are a few feet longer than what you think you need, install them and fuggetaboutit.

Thon,
Thanks for the advice. I hadn't considered shielded 2 conductor. Seems to be about the same cost as the RG59. What specs on shielded 2 or 4 conductor would be good for mid-fi?
I can't order already-terminated cable since this is basically being routed through the garage under my apartment and needs to be able to be fished through the floor. Plus it's awfully hard to find good quality interconnects that are 50' long. The actual distance between entry and exit is more like 30-40' depending on routing, so I should have plenty of extra slack with a 50' cable.
As for the centerpin connectors, they aren't so much crimpless as uniquely-crimped. Check out their animation at www.centerpin.com, seems like a solid enough connection. Anyone have any experience with Centerpin's connectors?

-- Dave

David, if I may chip in...

Try this technique. At one end of your long interconnects, connect one conductor AND the shield to the ground of the plug, but at the other end, connect ONLY the conductor to ground.

In other words, the two-conductor-plus-shield cable should have the shield connected at only one end. (This actually helps reduce noise and hum, but as it was pointed out by Thon, the twisted-pair trick is best used where your input stage is balanced for common-mode rejection, which means that the input stage ignores signals that are of the same polarity, and only responds to the difference signal, what is 'different' between the two conductors. This is why the pros use the Canon-type (XLR) 3-pin connectors: +, -, and ground.)

Which end? It's usually done so the shield is connected at the component being fed, but the best idea is to leave enough slack so you can try it both ways.

Larry
www.fineelectricco.com

This message was edited by Larry Fine on 12/14/01 18:04.54.

Actually the Belden 1694a cable is RG6 and the cable has better shielding then the Canare cables mentioned here.
Its SMPTE ratings for HDTV, Component and Composite are higher as well. It meets the specs over longer lengths than the Canare cables. The Belden 1694a cable is used by most Broadcast and production facilities including Lucas THX. These specs are all available on the Belden web site so you can compare them yourself.
Rememebr if you are going the DIY route make sure you invest in high quality connectors or you may as well use cheap and inferior cable.

Larry is right, with shielded 2 con the shield should only be connected at one end. I prefer that all shields be connected at the source (usually receiver) end as this ensures uniform potential. The main thing is NOT to connect both ends because any current flowing in the shield is potential for ground loops, which can take forever to debug.

Was he using balanced connections? This only applies to balanced audio schemes...and ground the out and float the in is the industry standard.

As it a applies to unbalanced connections? I don't think your going to see much difference with using that method. Normally you would just use the shield connection and one conductor. If your running unbalanced cables long distances, use a twisted config with foil and drain. Canare makes some great cables that are inherantly resistant to RFI.

Unbalanced cables use the shield as a ground return...

My equipment isn't really high end but I have had some friends with some pretty impressive setups; I would have to agree with thon that a big part of the problem with percieved cable problems is their placement. Be especially aware near power cords or sources.
Also for those on a budget reading this I have a possible solution: When I first started building my system I didn't have much money left for interconnects after buying components. Upon a friends advice I bought a heavier outdoor extension cord for speaker wire, you know the orange kind you plug your car in with,(about $8-9 for about 50 feet) and just cut the plug off and used that until I could afford a better cable and it sounded just fine. The wire in this cord would probably a heavier gauge than in most zip cords.

This message was edited by dominic stoltz on 12/19/01 08:55.56.